摘要
11Cr10Co2W2MoReVNbNB钢是一种含Re的超超临界汽轮机高温叶片用钢,使用温度高达630℃,也就是电站铁素体钢的使用温度极限。通过试验研究11Cr10Co2W2MoReVNbNB钢的高温瞬时拉伸性能、长期组织稳定性等应用性能,并介绍了各种应用性能的理论基础和钢的强化机理。试验结果表明:(1)随温度升高,钢的强度逐渐降低,在低温阶段塑性略有上升,在中温阶段塑性最差,进入高温阶段后塑性大幅升高;(2)经670℃、400h时效后,钢中M23C6等强化相的尺寸有所长大,但仍具有良好的高温拉伸性能,说明钢具有良好的组织稳定性;(3)钢主要通过弥散分布的颗粒状细小析出物M23C6相强化,Re主要存在于基体中,起固溶强化作用。试验证明11Cr10Co2W2MoReVNbNB钢是一种理想的高参数、大容量超超临界汽轮机高温叶片材料。
11Cr10Co2W2MoReVNbNB is a Re-containing steel used for USC steam turbine blades working at elevated temperature up to 630℃ which is the application limit for the ferritic steels for power plants parts. This paper studies the application properties including high temperature tensile properties, long term structural stability of the 11Cr10Co2W2MoReVNbNB, and also introduces the theoretical foundation of all the application properties and strengthening mechanism of the steel. The test results show that, 1 ） the strength of 11Cr10Co2W2MoReVNbNB steel decreases as the test temperature being raised, and the ductility increases slowly at the low temperature range, and becomes the lowest at the middle temperature range, and increases substantially at high temperature range; 2） after ageing tests at 670℃ for 400hrs, the strengthening phases such as M23 C6 in the steel grows slightly, and the tensile properties at high temperature keeps high, which indicate that the steel has very good structural stability; 3 ） the steel is primarily strengthened by the dispersed fine precipitates M23C6, and the Re element is mainly existence in the base for solution strengthening for the steel. The tests demonstrate that 11Cr10Co2W2MoReVNbNB steel is a desired material for high temperature blade for SUC steam turbines with higher steam parameter and large power.
出处
《汽轮机技术》
北大核心
2014年第4期318-320,共3页
Turbine Technology
关键词
汽轮机
高温
持久强度
叶片材料
steam turbine
high temperature
stress rupture strength
blade material
